White Residue on Weld?

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Welding some thin metal salvaged from an old deck hand rail and we ground off the old paint and torch welded the 1/16th inch metal tubing. After running the torch on it, I noticed a white residue all over the torch and weld. Is this zinc oxide? Am I going to die?  ... Just kidding but seriously if it is zinc then I cant weld it because I cant grind inside the tube. We didnt do much more than 5 minutes of welding on it and I wear a mask when flux core welding anyway and I still had it on with the torch.Victor Journeyman OA TorchVictor Edge RegulatorsLincoln 180HD (240v) MIG/FCAWShark LT v7 CADMiller Digital Elite Helmet35 Milligrams of Insanity
Reply:It was probably galvanized. DON"T breathe the white smoke!  It gives you the sh*ts and the shakes.  Been there done that.I doubt you harmed your self.  Not much you can do about that.DavidReal world weldin.  When I grow up I want to be a tig weldor.
Reply:Originally Posted by David RIt was probably galvanized. DON"T breathe the white smoke!  It gives you the sh*ts and the shakes.  Been there done that.I doubt you harmed your self.  Not much you can do about that.David
Reply:If you must, than you must. Try standing up-wind of the smoke, indoor or out door.
Reply:http://www.osha.gov/SLTC/healthguide...cognition.html
Reply:Look inside your tubes after welding and see if you have a lot of fluffy white stuff.  You can also tell galvanized because it will sometimes hiss and pop when you're welding.  When you get temperatures up to steel melting temp, the zinc will almost instantly vaporize (this makes the hissing/popping sounds).White stuff on your torch sounds like you didn't fully grind all the zinc off.  This may mean your welds are fully of porosity.  The zinc will vaporize and make your weld metal fluff up.  If it's non-structrual and has good surface appearance I probably wouldn't worry.You said "torch welded" but then also said "flux-core".  I assume you're doing flux-core with wire feed "torch" and not doing O/A welding.  With O/A you may be able to get rid of the zinc by first heating the weld area up to burn off the zinc, and then hitting it with a sanding disc or wire wheel before welding.  There may be some chemical way of removing the zinc, but I suspect it'll be too expensive to use on scrap tubing, or it'll take too much time to do its work.I've never had any trouble from galvanized.  I use a respirator AND keep a little draft to remove the smoke.  A "mask" might not be enough depending on what type of mask you have.  A dust mask isn't good enough.  Get one that says it's good for metal fume (cheap ones start around $9, better ones are $20 or 30).  I want to get a supplied air setup, but those are pricy.Dynasty200DX w/coolmate1MM210MM VintageESAB miniarc161ltsLincoln AC225Victor O/A, Smith AW1ACutmaster 81IR 2475N7.5FPRage3Jancy USA1019" SBAEAD-200LE
Reply:I weld galvi tube all the time with fluxcore wire.  I wear a 3M half mask respirator with the pink filters and all is well.  This is best done outdoors and a little breeze is helpful too.  And yes, it can be and is welded just fine without grinding it off first, I weld it without grinding most of the time, with fluxcore or stick.  I grind it if I'm using tig or gas mig though.MM350P/Python/Q300MM175/Q300DialarcHFHTP MIG200PowCon300SMHypertherm380ThermalArc185Purox oaF350CrewCab4x4LoadNGo utilitybedBobcat250XMT304/Optima/SpoolmaticSuitcase12RC/Q300Suitcase8RC/Q400Passport/Q300Smith op
Reply:Always when applicable remove the gal by light grinding or sanding stop when you see sparks thats when you have reached base metal,for inside of tubes and pipes use a rotary grinder.Make sure you use a dust mask when doing this as Gal dust can be equally as bad as fumes.Welder First Class
Reply:...well, you pretty much just have to sand/grind all the zinc off....you'll be able to see the edge of zinc....it's a little more silver colored than the grayer steel....weldover galvanized...you'll get a lot of spatter....sticks to welded parts, and quickly clogs MIG nozzles....hard to get liquid tight welds,   An alternative solution....use carbon arc, D.C. reverse with C.C.power source like you'd use for SMAW or TIG.......silicon bronze filler....very common on thin HVAC duct work...clamp carbon in rod-holder, 2-3" exposed .....grind end to point like a pencil....use 30-40 amps....5/32" or 3/16" carbon....stuff is cheap....and don't need to remove zinc...still will be a smoky deal....don't breathe it, drink some milk too....helps get the zinc smoke out of your system...  I've welded 1/2-2" EMT with this process....welds look almost like a TIG....Dougspair